Drill steel centralizer



March 3, 1942. A. FEucHT El'AL DRILL STEEL CENTRALIZER Original FiledMarch 3, 1939 ATTORNEY INVENTOES ALBERT f'fl/CHT THEOOOQEA. SCI/M07Patented Mar. 3, 1942 UNl'lfE- S ninLL. STEEL CENTRALIZER.

' Albert Feucli-t, Garfield Heights, and Theodore A. Schmidt, Cleveland,Ohio, assignors to The Cleveland Rock Drill Company,

Cleveland,

' Ohio, a corporation of Ohio Substitute for. abandoned applicationSerial No. 259,614, March 3, 1939. This application May 19, 1941, SerialNo. 394,172

(iClaims.

coaxial alignment with the rock drill during the starting of a drillhole.

This application is a substitute forour prior application Serial No.259,614 filed March 3,1939, and since abandoned.

One object of this invention is to provide a' rockdrill with anefiicient drill steel centralizer cooperating with the drill steel formaintaining it in perfect alignment with the rock drill when starting adrill hole.

Another object of this invention is to produce a drill steel centralizerconstructed and disposed in a' manner enabling it' to be automaticallymoved into inoperative position by the rockdrill duringv its feedingmotion to'the work, the centralizer being characterized by a simpleconstruction which is. strong, durable and efficient.

Other objects and advantages mor or less ancillaryto the foregoingreside in theispecific construction and aggroupment of ther elementspeculiar to this structure, as will become apparent from a more completeexamination of this specification.

In the drawing:.

Fig. 1 is a side elevational view of the: front portion of a rock drillembodying the invention.

Fig. 2 is a top plan View looking in the direction of' the arrows 22 inFig. 1.

Fig. 3 is a cross sectional view taken in a plane indicated by line 33in Fig. 1.

Fig. 4 is a fragmental longitudinally sectional view taken in a planeindicated by line 4-4 in Fig. 2.

Fig. 5 is a view similar to Fig. 4 taken in: a plane indicated by line5.5 in' Fig. 2.

Fig. 6 is a view similarito Fig. 1 illustrating the centralizer ininoperative position.

Fig. '7 is an end view looking in the direction of the arrows l'l inFig. 6.

Referring to the drawing, [0 represents the front end of a stationaryshell on which is slidably mounted a rock drill, the front head ll ofwhich is shown in Fig. 1. Mounted within this front head ll, there isthe usual drill steel l2 extending longitudinally therefrom andterminated by a bit [3 engageable with th work. In practice, when thedrill steel, which is loosely mounted within the front end II, isrotated and fed to the work in the usual manner, its bit l3 engaging theuneven face In of the work will cause the drill steel to move laterallyrelative to the center axis of the drill, thereby making it difficultfor the operator to start the drill hole at a predetermined or givenlocation. To overcome this difficulty, there is fastened to the end ofthe shell 10 a longitudinally extending support l5 connected to the endof the shell by bolts [-6. This support extends under the drill steel l2about six inches from the end of the shell [0 and has its front endprovided with two laterally spaced lugs IT having a cross bolt l Bextending therethrough and secured in position by' 'a nut l9. Mounted onthe bolt is, there is a pivot orbushing locked to one of the lugs l'l-bya key 2|. On this bushing is rotatably mounted a guid arm 22 capable oflocation within the path of the rock drill front end' I l, and havingits upper end formed with semicircular groove 23 of a dimension enablingit to fit partly around the drill steel. On one side of the bushing 20,there is also mounted on the bolt it a stationary spiral gear 24;clamped between the stationary bushing 20 and an enlarged cylindricalportion or head 25'formed on the bolt 18', which head together with thegear 24 extend into a counter bore 26 formed onone side of the arm 22.

Intermediate its ends, the bushing 20 is provided with two flats 21 and28 disposed at 90 from one other and engageable by a spring pressedplunger 29 located within a plug 30 which is screwed in the lowerportion of the arm 22.

One of the longest sides of the arm 22 is pro-- vided with a boss 3|extending the full length thereof and having rotatable therein a pivotor stem 32-. The lower end of the boss 3| is counterbored as at 3i toaccommodate the corresponding end of the stem 32, which hasmountedthereon against relative rotation a pinion 33 meshing with thegearv 24'. This pinion is held against endwise movement by a washer34'engaging the bottom of the counterbore 3|" and by a nut 35 threadedon the extreme endof'the stem 32. The pinion 33 may be assembled on thelower end of the shaft 32 by removing a plug 36 threaded into thecounterbore 3i. Formed integrally with the stem 32, there is a guidefinger 31 resting on theupper end of the boss 3|, which finger isformedwith a semicircular groove 38 capable of being swung laterallyover the drill. steel I2 to prevent upward movement of the drill steelrelative to the guide arm 22. I In the operation of the device, when thecentralizer is positioned as shown in Figs. 1 to 3 inclusive, it will beunderstood that the drill steel l2 now located within the groove 23 ofth guide arm 22 and in the groove 38 of the guide finger 31, is guidedagainst lateral movement and made to remain in coaxial alignment withthe center axis of the rock drill, thereby enabling the operator tostart the drill hole at any given location without danger of the drillbit [3 walking away from the intended spot. In this operative positionof the centralizer, th arm 22 is located within the path of the drillsfront end H, thus causing the arm, during the feeding motion of thedrill, to be contacted by the front end H and swung thereby in aclockwise direction in Fig. 1 around the pivot 20. In this instance, thespring pressed plunger 29 normally engaging the fiat 21 of thestationary bushing 20, will be made to pass over the junction of thflats 21 and 28, and thereafter to engage the portion of the flat 23adjacent the flat 21 to cause a camming action resulting in thecentralizer being moved into the inoperative or horizontal positionshown in Fig. 6. As the arm 22 is swung into a horizontal position, thepinion 33 engaging the stationary spiral gear 28 will cause rotation ofthe shaft 32 and consequently of its finger 31 in a counterclockwisedirection in Fig, 2. This movement of the finger resulting from theswinging movement of the arm 22 is calculated to take place at a rate ofspeed enabling movement of the finger 31 away from the drill steel,while the arm 22 together with the finger 31 are swung downwardly orinto inoperative position to enable free passage of the rock drill frontend ll over the centralizer.

After the drill has been moved back preparatory to the drilling ofanother hole, the centralizer may be brought back into operativeposition with respect to the drill steel by manually swinging the guidearm 22 from the position in Fig. 6 to the position in Fig. 1. Duringthis swinging motion of the arm 22, the pinion 33 engaging the gear 26will transmit rotation to the finger 31, causing it to move from theposition in Fig. 7 to the position in Fig. 2, that is into operativeposition relative to the drill steel l2.

From the foregoing description, it will be understood that with thecentralizer in operative position, the drilling operation may take placewithout requiring the operator to move the centralizer out of the pathof the rock drill. In other words, the centralizer is automaticallyshifted into inoperative position to enable free passage of therock-drill front end ll. Due to the operative engagement of the springpressed plunger 29 with the fiats 21 or 28 of the stationary bushing 20,the centralizer is normally held in operative or inoperative positionagainst accidental rotation. The movable parts of the centralizer, suchas the shaft 32, the pinion 33 and the locking plunger 29, beingentirely enclosed within the arm 22, are protected from dust or otherforeign matter which would otherwise affect their free operation.

Although the foregoing description is necessarily of a detailedcharacter, in order to completely set forth the invention, it is to beunderstood that the specific terminology is not intended to berestrictive or confining and it is to be further understood that variousrearrangements of parts and modifications of structural detail may beresorted to without departing from the scope or spirit of the inventionas herein claimed.

We claim:

1. A centralizer for drill steels, comprising a support, a pivot in saidsupport, a guide arm operatively mounted on said pivot, a pivot in sailarm, a guide finger operatively mounted on said last pivot,interengaging means on said pivots preventing rotation of said fingerindependently of said arm, and resilient means operatively associatedwith said arm for resisting its rotation on its pivot.

2. A centralizer for drill steels, comprising a support, a guide armrotatably mounted on said support, a guide finger rotatably mounted onsaid arm, a stationary gear on the support, and a pinion on said fingermeshing with said gear for automatically effecting rotation of saidfinger upon rotation of said arm. a

3. A centralizer for drill steels, comprising a support, a drill steelengaging arm rotatably mounted on said support, a drill steel engagingfinger mounted on said arm for rotation therewith in one direction andrelative thereto in another direction, and interengaging cog-wheels onsaid support and finger effecting rotation of said finger relative tosaid arm upon rotation of said support, a drill steel engaging armrotatably including a member deriving rotation relative to said arm fromthe rotation of said arm, said member being drivingly connected to saidfinger.

6. A drill steel centralizer comprising a support, a drill steel guidingarm and finger rotatable relative to said support on axes perpendicularto each other, and a rotation mechanism for said finger including amember drivingly connected to said finger deriving rotation relative tosaid arm from the rotation of said arm.

ALBERT FEUCHT. THEODORE A.; SCHMIDT.

